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1.
BMC Cardiovasc Disord ; 24(1): 203, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38594610

ABSTRACT

BACKGROUND: In patients with hypertrophic cardiomyopathy (HCM), ischemic myocardial fibrosis assessed by late gadolinium enhancement (I-LGE) using cardiovascular magnetic resonance (CMR) have been reported. However, the clinical significance of I-LGE has not been completely understood. We aim to evaluate the I-LGE differ phenotypically from HCM without LGE or nonischemic myocardial fibrosis assessed by late gadolinium enhancement (NI-LGE) in the left ventricle (LV). METHODS: The patients with HCM whom was underwent CMR were enrolled, using cine cardiac magnetic resonance to evaluate LV function and LGE to detect the myocardial fibrosis. Three groups were assorted: 1) HCM without LGE; 2) HCM with LGE involved the subendocardial layer was defined as I-LGE; 3) HCM with LGE not involved the subendocardial layer was defined as NI-LGE. RESULTS: We enrolled 122 patients with HCM in the present study. LGE was detected in 58 of 122 (48%) patients with HCM, and 22 (18%) of patients reported I-LGE. HCM with I-LGE had increased higher left ventricular mass index (LVMI) (P < 0.0001) than HCM with NI-LGE or without LGE. In addition, HCM with I-LGE had a larger LV end- systolic volume (P = 0.045), lower LV ejection fraction (LVEF) (P = 0.026), higher LV myocardial mass (P < 0.001) and thicker LV wall (P < 0.001) more than HCM without LGE alone. The I-LGE were significantly associated with LVEF (OR: 0.961; P = 0.016), LV mass (OR: 1.028; P < 0.001), and maximal end-diastolic LVWT (OR: 1.567; P < 0.001). On multivariate analysis, LVEF (OR: 0.948; P = 0.013) and maximal end-diastolic LVWT (OR: 1.548; P = 0.001) were associated with higher risk for I-LGE compared to HCM without LGE. Noticeably, the maximal end-diastolic LVWT (OR: 1.316; P = 0.011) was the only associated with NI-LGE compared to HCM without LGE. CONCLUSIONS: I-LGE is not uncommon in patients with HCM. HCM with I-LGE was associated with significant LV hypertrophy, extensive LGE and poor LV ejection fraction. We should consider focal ischemic myocardial fibrosis when applying LGE to risk stratification for HCM.


Subject(s)
Cardiomyopathy, Hypertrophic , Contrast Media , Humans , Gadolinium , Magnetic Resonance Imaging, Cine , Cardiomyopathy, Hypertrophic/diagnosis , Myocardium/pathology , Fibrosis , Magnetic Resonance Spectroscopy
2.
Int J Med Sci ; 20(7): 836-848, 2023.
Article in English | MEDLINE | ID: mdl-37324184

ABSTRACT

Atherosclerosis is a chronic, inflammatory disease characterized by a lipid-driven infiltration of inflammatory cells in large and medium arteries and is considered to be a major underlying cause of cardiovascular diseases. Cuproptosis, a novel form of cell death, is highly linked to mitochondrial metabolism and mediated by protein lipoylation. However, the clinical implication of cuproptosis-related genes (CRGs) in atherosclerosis remains unclear. In this study, genes collected from the GEO database intersected with CRGs were identified in atherosclerosis. GSEA, GO and KEGG pathway enrichment analyses were performed for functional annotation. Through the random forest algorithm and the construction of a protein-protein interaction (PPI) network, eight selected genes (LOXL2, SLC31A1, ATP7A, SLC31A2, COA6, UBE2D1, CP and SOD1) and a vital cuproptosis-related gene FDX1 were then further validated. Two independent datasets (GSE28829 (N = 29), GSE100927 (N = 104)) were collected to construct the signature of CRGs for validation in atherosclerosis. Consistently, the atherosclerosis plaques showed significantly higher expression of SLC31A1, SLC31A2 and lower expression of SOD1 than the normal intimae. The area under the curve (AUC) of SLC31A1, SLC31A2 and SOD1 performed well for the diagnostic validation in the two datasets. In conclusion, the cuproptosis-related gene signature could serve as a potential diagnostic biomarker for atherosclerosis and may offer novel insights into the treatment of cardiovascular diseases. Based on the hub genes, a competing endogenous RNA (ceRNA) network of lncRNA-miRNA-mRNA and a transcription factor regulation network were ultimately constructed to explore the possible regulatory mechanism in atherosclerosis.


Subject(s)
Apoptosis , Atherosclerosis , Cardiovascular Diseases , Plaque, Atherosclerotic , Humans , Atherosclerosis/diagnosis , Atherosclerosis/genetics , Biomarkers , Carrier Proteins , Mitochondrial Proteins , Superoxide Dismutase-1 , Copper
3.
Biochem Biophys Res Commun ; 617(Pt 2): 69-76, 2022 08 30.
Article in English | MEDLINE | ID: mdl-35691117

ABSTRACT

Diabetic retinopathy (DR) is a key reason for legal blindness worldwide. Currently, it is urgently necessary to determine the etiology and pathological molecular mechanism of DR to search for resultful therapies. Dickkopf-1 (DKK1) is inhibitive for canonical Wnt signaling via negative feedback, and has been reported as a biomarker for DR. However, the related mechanisms are still unclear. In this work, our data showed that DKK1 was decreased in the vitreous tissues at an early stage of diabetes triggered by streptozotocin (STZ) injection in rats. We subsequently found that DKK1 intravitreal injection significantly ameliorated the physiological function of retina in STZ-challenged rats, accompanied by improved retinal structure. Surprisingly, our results indicated that DKK1 injection remarkably suppressed PANoptosis in retinal tissues of STZ-challenged rats with DR, as proved by ameliorated pyroptosis, apoptosis and necroptosis, which were mainly through the blockage of cleaved Gasdermin-D (GSDMD), Caspase-3 and receptor-interacting protein kinase-3 (RIPK3). Additionally, Wnt signaling including the expression of Wnt, ß-catenin and LDL receptor-related protein 5/6 (LRP5/6) was also highly prohibited in retina of DKK1-injected rats with DR. Furthermore, retinal neovascularization and acellular vessel in DR rats were also considerably abolished after DKK1 injection, accompanied by reduced expression levels of retinal vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP2) and matrix metalloproteinase-9 (MMP9). More in vitro experiments showed that DKK1 treatment markedly repressed the proliferative and migratory ability of endothelial cells via inhibiting angiogenesis-related molecules. Together, all our results broaden the knowledge of the correlation between DKK1 and DR, and then provide a novel therapeutic strategy for the suppression of management of DR.


Subject(s)
Diabetes Mellitus, Experimental , Diabetic Retinopathy , Intercellular Signaling Peptides and Proteins/metabolism , Retinal Neovascularization , Animals , Diabetes Mellitus, Experimental/metabolism , Diabetic Retinopathy/metabolism , Endothelial Cells/metabolism , Matrix Metalloproteinase 2/metabolism , Rats , Retina/metabolism , Retinal Neovascularization/metabolism , Retinal Neovascularization/prevention & control , Streptozocin , Vascular Endothelial Growth Factor A/metabolism
4.
Proc Natl Acad Sci U S A ; 116(29): 14573-14582, 2019 07 16.
Article in English | MEDLINE | ID: mdl-31266892

ABSTRACT

Androgen receptor (AR) is a ligand-activated transcription factor and a key driver of prostate cancer (PCa) growth and progression. Understanding the factors influencing AR-mediated gene expression provides new opportunities for therapeutic intervention. Poly(ADP-ribose) Polymerase (PARP) is a family of enzymes, which posttranslationally modify a range of proteins and regulate many different cellular processes. PARP-1 and PARP-2 are two well-characterized PARP members, whose catalytic activity is induced by DNA-strand breaks and responsible for multiple DNA damage repair pathways. PARP inhibitors are promising therapeutic agents that show synthetic lethality against many types of cancer (including PCa) with homologous recombination (HR) DNA-repair deficiency. Here, we show that, beyond DNA damage repair function, PARP-2, but not PARP-1, is a critical component in AR transcriptional machinery through interacting with the pioneer factor FOXA1 and facilitating AR recruitment to genome-wide prostate-specific enhancer regions. Analyses of PARP-2 expression at both mRNA and protein levels show significantly higher expression of PARP-2 in primary PCa tumors than in benign prostate tissues, and even more so in castration-resistant prostate cancer (CRPC) tumors. Selective targeting of PARP-2 by genetic or pharmacological means blocks interaction between PARP-2 and FOXA1, which in turn attenuates AR-mediated gene expression and inhibits AR-positive PCa growth. Next-generation antiandrogens act through inhibiting androgen synthesis (abiraterone) or blocking ligand binding (enzalutamide). Selective targeting of PARP-2, however, may provide an alternative therapeutic approach for AR inhibition by disruption of FOXA1 function, which may be beneficial to patients, irrespective of their DNA-repair deficiency status.


Subject(s)
Hepatocyte Nuclear Factor 3-alpha/antagonists & inhibitors , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Poly(ADP-ribose) Polymerases/metabolism , Prostatic Neoplasms, Castration-Resistant/drug therapy , Receptors, Androgen/metabolism , Animals , Benzimidazoles/pharmacology , Benzimidazoles/therapeutic use , Cell Line, Tumor , Datasets as Topic , Disease-Free Survival , Gene Expression Regulation, Neoplastic/drug effects , Gene Knockout Techniques , Humans , Kaplan-Meier Estimate , Male , Mice , Phthalazines/pharmacology , Phthalazines/therapeutic use , Piperazines/pharmacology , Piperazines/therapeutic use , Poly (ADP-Ribose) Polymerase-1/genetics , Poly (ADP-Ribose) Polymerase-1/metabolism , Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use , Poly(ADP-ribose) Polymerases/genetics , Prostate/pathology , Prostatic Neoplasms, Castration-Resistant/genetics , Prostatic Neoplasms, Castration-Resistant/mortality , Prostatic Neoplasms, Castration-Resistant/pathology , RNA, Small Interfering/metabolism , RNA-Seq , Signal Transduction/drug effects , Signal Transduction/genetics , Tissue Array Analysis , Xenograft Model Antitumor Assays
5.
Angew Chem Int Ed Engl ; 59(45): 19974-19982, 2020 Nov 02.
Article in English | MEDLINE | ID: mdl-32721064

ABSTRACT

The nonradiative recombination of electrons and holes has been identified as the main cause of energy loss in hybrid organic-inorganic perovskite solar cells (PSCs). Sufficient built-in field and defect passivation can facilitate effective separation of electron-hole pairs to address the crucial issues. For the first time, we introduce a homochiral molecular ferroelectric into a PSC to enlarge the built-in electric field of the perovskite film, thereby facilitating effective charge separation and transportation. As a consequence of similarities in ionic structure, the molecular ferroelectric component of the PSC passivates the defects in the active perovskite layers, thereby inducing an approximately eightfold enhancement in photoluminescence intensity and reducing electron trap-state density. The photovoltaic molecular ferroelectric PSCs achieve a power conversion efficiency as high as 21.78 %.

6.
Am J Physiol Gastrointest Liver Physiol ; 316(6): G816-G825, 2019 06 01.
Article in English | MEDLINE | ID: mdl-30943050

ABSTRACT

Intra-acinar trypsinogen activation occurs in the earliest stages of pancreatitis and is believed to play important roles in pancreatitis pathogenesis. However, the exact role of intra-acinar trypsin activity in pancreatitis remains elusive. Here, we aimed to examine the specific effects of intra-acinar trypsin activity on the development of pancreatitis using a transgenic mouse model. This transgenic mouse model allowed for the conditional expression of a mutant trypsinogen that can be activated specifically inside pancreatic acinar cells. We found that expression of this active mutated trypsin had no significant effect on triggering spontaneous pancreatitis. Instead, several protective compensatory mechanisms, including SPINK1 and heat shock proteins, were upregulated. Notably, these transgenic mice developed much more severe acute pancreatitis, compared with control mice, when challenged with caerulein. Elevated tissue edema, serum amylase, inflammatory cell infiltration and acinar cell apoptosis were dramatically associated with increased trypsin activity. Furthermore, chronic pathological changes were observed in the pancreas of all transgenic mice, including inflammatory cell infiltration, parenchymal atrophy and cell loss, fibrosis, and fatty replacement. These changes were not observed in control mice treated with caerulein. The alterations in pancreata from transgenic mice mimicked the histological changes common to human chronic pancreatitis. Taken together, we provided in vivo evidence that increased intra-acinar activation of trypsinogen plays an important role in the initiation and progression of both acute and chronic pancreatitis. NEW & NOTEWORTHY Trypsinogen is activated early in pancreatitis. However, the roles of trypsin in the development of pancreatitis have not been fully addressed. Using a genetic approach, we showed trypsin activity is critical for the severity of both acute and chronic pancreatitis.


Subject(s)
Acinar Cells/metabolism , Pancreas, Exocrine , Pancreatitis, Chronic , Pancreatitis , Trypsin/metabolism , Animals , Disease Models, Animal , Mice , Pancreas, Exocrine/metabolism , Pancreas, Exocrine/pathology , Pancreatitis/metabolism , Pancreatitis/pathology , Pancreatitis, Chronic/metabolism , Pancreatitis, Chronic/pathology , Severity of Illness Index , Trypsinogen/metabolism
7.
Sensors (Basel) ; 17(3)2017 Mar 07.
Article in English | MEDLINE | ID: mdl-28272330

ABSTRACT

A novel micro-electro-mechanical systems (MEMS) inertial microswitch with a flexible contact-enhanced structure to extend the contact duration has been proposed in the present work. In order to investigate the stiffness k of the stationary electrodes, the stationary electrodes with different shapes, thickness h, width b, and length l were designed, analyzed, and simulated using ANSYS software. Both the analytical and the simulated results indicate that the stiffness k increases with thickness h and width b, while decreasing with an increase of length l, and it is related to the shape. The inertial micro-switches with different kinds of stationary electrodes were simulated using ANSYS software and fabricated using surface micromachining technology. The dynamic simulation indicates that the contact time will decrease with the increase of thickness h and width b, but increase with the length l, and it is related to the shape. As a result, the contact time decreases with the stiffness k of the stationary electrode. Furthermore, the simulated results reveal that the stiffness k changes more rapidly with h and l compared to b. However, overlarge dimension of the whole microswitch is contradicted with small footprint area expectation in the structure design. Therefore, it is unreasonable to extend the contact duration by increasing the length l excessively. Thus, the best and most convenient way to prolong the contact time is to reduce the thickness h of the stationary electrode while keeping the plane geometric structure of the inertial micro-switch unchanged. Finally, the fabricated micro-switches with different shapes of stationary electrodes have been evaluated by a standard dropping hammer system. The test maximum contact time under 288 g acceleration can reach 125 µs. It is shown that the test results are in accordance with the simulated results. The conclusions obtained in this work can provide guidance for the future design and fabrication of inertial microswitches.

8.
AAPS PharmSciTech ; 18(7): 2774-2782, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28361455

ABSTRACT

Methotrexate (MTX; an anti-folate) and etanercept (ET; a TNF-α inhibitor) are used against arthritis; however, limitations like short biological half-life, low cutaneous absorption, and acidic instability limit their clinical relevance. Therefore, the aim of the investigation was to develop albumin coupled lipid nanoemulsion of MTX and ET for improved efficacy by virtue of their controlled release and specificity at the arthritic site. This emulsion was prepared by high-speed homogenization and stabilized using cholesterol. Lipid nanoemulsion of MTX and ET (MTX+ET-LNE) was coupled with albumin (MTX+ET-ALNE). MTX+ET-ALNE was characterized on the basis of particle size (410 ± 25.4 nm), PDI (0.160), and zeta potential (+38.6 ± 5.6 mV) and evaluated for pH (6.15), drug content (97.7 ± 2.17%), entrapment efficiency (76 ± 4.6%), in vitro release, and in vitro cytotoxicity. About 82.6 ± 9.60% release of MTX+ET was observed in 24 h from the developed MTX+ET-ALNE which may help maintain therapeutic level of drugs in blood at least for one day. No toxicity was observed when Raw 264.7 cells were treated with MTX+ET-ALNE, and no causalities of mice were observed at experimental in vivo dose (10 mg/kg BW) of MTX+ET in MTX+ET-ALNE-treated group. MTX+ET-ALNE treatment has alleviated arthritic scores and inflammatory cytokines level in a very significant manner when compared with MTX+ET-LNE and MTX+ET solutions. MTX+ET-ALNE-treated group restored histological alterations (cartilage/bone erosion, inflammatory cell infiltration, synovial hyperplasia, and narrower joint space) as observed in diseased treated groups. In conclusion, MTX+ET-ALNE can be opted as efficacious and clinically pertinent option to the current medication systems of arthritis.


Subject(s)
Antirheumatic Agents/administration & dosage , Arthritis, Rheumatoid/drug therapy , Etanercept/administration & dosage , Methotrexate/administration & dosage , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Albumins/chemistry , Animals , Cholesterol/chemistry , Drug Liberation , Emulsions , Etanercept/chemistry , Female , Lipids/chemistry , Methotrexate/chemistry , Mice , Mice, Inbred BALB C , Rats , Rats, Sprague-Dawley
9.
Cell Biol Int ; 40(12): 1294-1302, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27600360

ABSTRACT

MicroRNA-21 (miR-21) was reported to act as an oncogene during the development of many human tumors. However, little was revealed about the function of miR-21 in retinoblastoma (RB). In this study, we examined the expression of miR-21 in RB tissues and explored the relationship between miR-21 and phosphatase and tensin homolog (PTEN)/phosphatidylinositol-3-OH kinase (PI3K)/AKT signal. Quantitative real-time PCR (qRT-PCR) results showed that the level of miR-21 in RB tissues was higher than that in retinal normal tissues. In Weri-Rb-1 cells, miR-21 inhibitor suppressed the expression of miR-21 and cell viability, but improved cell apoptotic rates by modulating the levels of PDCD4, Bax, and Bcl-2. Meanwhile, miR-21 inhibitor suppressed cell migration and invasion via inhibiting the protein levels of MMP2 and MMP9 and significantly affected the expression of PTEN, PI3K, and p-AKT. Taken together, miR-21 inhibitor suppressed cell proliferation, migration, and invasion via the PTEN/PI3K/AKT signal. These findings revealed the molecular basis of miR-21 functioning in the progression of RB and provided a new means for cell therapy in RB.


Subject(s)
MicroRNAs/metabolism , PTEN Phosphohydrolase/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Retinoblastoma/genetics , Retinoblastoma/pathology , Signal Transduction , Apoptosis , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation , Child , Child, Preschool , Disease Progression , Gene Expression Regulation, Neoplastic , Humans , Infant , MicroRNAs/genetics , Neoplasm Invasiveness , Neoplasm Proteins/metabolism
10.
J Nat Prod ; 78(10): 2405-10, 2015 Oct 23.
Article in English | MEDLINE | ID: mdl-26378981

ABSTRACT

Aspertetranones A-D (1-4), four new highly oxygenated putative rearranged triketide-sesquiterpenoid meroterpenes, were isolated from the marine algal-associated fungus Aspergillus sp. ZL0-1b14. On the basis of a comprehensive spectroscopic analysis, the planar structures of aspertetranones were determined to possess an unusual skeleton in the terpenoid part. The relative and absolute configurations of the aspertetranones were assigned on the basis of NOESY analysis, X-ray crystallography, and circular dichroism spectroscopy. Compounds 1-4 were evaluated for anti-inflammatory activity in LPS-stimulated RAW264.7 macrophages. Aspertetranone D exhibited an inhibitory effect against IL-6 production with 69% inhibition at 40 µM.


Subject(s)
Aspergillus/chemistry , Sesquiterpenes/isolation & purification , Algorithms , Animals , Anti-Inflammatory Agents/pharmacology , China , Crystallography, X-Ray , Interleukin-6/antagonists & inhibitors , Lipopolysaccharides/pharmacology , Macrophages/drug effects , Marine Biology , Mice , Molecular Conformation , Molecular Structure , Nitric Oxide/analysis , Nuclear Magnetic Resonance, Biomolecular , Sesquiterpenes/chemistry , Sesquiterpenes/pharmacology
11.
Sensors (Basel) ; 15(4): 9547-62, 2015 Apr 22.
Article in English | MEDLINE | ID: mdl-25912351

ABSTRACT

This paper experimentally and numerically investigated the heat transfer and friction characteristics of microfluidic heat sinks with variously-shaped micro-ribs, i.e., rectangular, triangular and semicircular ribs. The micro-ribs were fabricated on the sidewalls of microfluidic channels by a surface-micromachining micro-electro-mechanical system (MEMS) process and used as turbulators to improve the heat transfer rate of the microfluidic heat sink. The results indicate that the utilizing of micro-ribs provides a better heat transfer rate, but also increases the pressure drop penalty for microchannels. Furthermore, the heat transfer and friction characteristics of the microchannels are strongly affected by the rib shape. In comparison, the triangular ribbed microchannel possesses the highest Nusselt number and friction factor among the three rib types.

12.
Molecules ; 20(6): 10839-47, 2015 Jun 11.
Article in English | MEDLINE | ID: mdl-26111172

ABSTRACT

A new natural halogen-containing stilbene derivative was isolated from the leaves of Cajanus cajan (L.) Millsp. and identified as 3-O-(3-chloro-2-hydroxyl-propanyl)-longistylin A by comprehensive spectroscopic and chemical analysis, and named cajanstilbene H (1). It is the first halogen-containing stilbene derivative found from plants. In human mesenchymal stem cells (hMSC) from bone marrow, 1 did not promote cell proliferation, but distinctly enhanced osteogenic differentiation of hMSC in time- and dose-dependent manners. In six human cancer cell lines, 1 showed a moderate inhibitory effect on cell proliferation, with IC50 values of 21.42-25.85 µmol·L(-1).


Subject(s)
Cell Differentiation/drug effects , Mesenchymal Stem Cells/drug effects , Osteogenesis/drug effects , Plant Extracts/administration & dosage , Cajanus/chemistry , Halogens/administration & dosage , Halogens/chemistry , Humans , Plant Extracts/chemistry , Plant Leaves/chemistry , Stilbenes/administration & dosage , Stilbenes/chemistry
13.
J Cell Biochem ; 115(11): 1928-36, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24905663

ABSTRACT

Increasing evidences have illuminated the fundamental role of inflammation in mediating all stages of atherosclerosis. miR-155, a typical multi-functional miRNA, has recently emerged as a novel component of inflammatory signal transduction in the pathogenesis of atherosclerosis. However, little is known about whether endothelial highly expressed miR-155 can regulate endothelial inflammation-related transcription factors and the predicted role of miR-155 as a negative feedback regulator in endothelial inflammation involved in atherosclerosis. Bioinformatics analysis showed that RELA (nuclear factor-κB p65) is a potential target gene of miR-155 and this was confirmed by a luciferase reporter assay. Our results show that microRNA-155 mediate endothelial inflammation and decrease NFкB p65 and adhesion molecule expression in TNFα-stimulated endothelial cells. Transfection with miR-155 significantly inhibited TNFα-induced monocyte adhesion to endothelium. Inhibition of miR-155 enhanced p65 level and endothelial inflammatory response which was counteracted through the depletion of P65 by Si-P65. On the other hand, knockdown of eNOS, another target of miR-155, while transfecting with miR-155 inhibitor resulted in more significant inflammatory response. miR-155 is highly expressed in TNFα treated HUVECs, deprived of endogenous p65 could reverse TNFα-induced upregulation of miR-155. Thus, TNFα induced miR-155 may serve as a negative feedback regulator in endothelial inflammation involved in atherosclerosis by targeting nuclear transcription factor P65. These results provide a rationale for intervention of intracellular microRNA as possible anti-atherosclerotic targets.


Subject(s)
Inflammation/genetics , MicroRNAs/genetics , MicroRNAs/metabolism , Transcription Factor RelA/genetics , Tumor Necrosis Factor-alpha/pharmacology , 3' Untranslated Regions , Cytokines/metabolism , HEK293 Cells , Human Umbilical Vein Endothelial Cells , Humans , Inflammation/metabolism , Models, Biological , Transcription Factor RelA/metabolism
14.
Bioorg Med Chem Lett ; 24(10): 2388-91, 2014 May 15.
Article in English | MEDLINE | ID: mdl-24745970

ABSTRACT

In this study we report the synthesis and activity against bovine viral diarrhea virus (BVDV) of a novel series of bicycle δ-sultones containing γ-lactones. BVDV is responsible for major losses in cattle. Some of the synthesized δ-sultones showed pronounced anti-BVDV activity with EC50 values of 0.12-1.0µM and no significant cytotoxicity. Among them, the ortho bromosubstituted derivative 4f (EC50=0.12µM) showed better antiviral activity than other derivatives and was 10 fold more that of than positive control ribavirin (EC50=1.3µM). BVDV is also considered to be a valuable surrogate for the hepatitis C virus (HCV) in antiviral drug studies. The above results provided a novel candidate for the development of anti-HCV agents.


Subject(s)
Antiviral Agents/chemical synthesis , Antiviral Agents/pharmacology , Diarrhea Viruses, Bovine Viral/drug effects , Hepacivirus/drug effects , Animals , Cattle , Disease Models, Animal , Drug Design
15.
IEEE Trans Image Process ; 33: 216-227, 2024.
Article in English | MEDLINE | ID: mdl-37906476

ABSTRACT

Recently, with the assumption that samples can be reconstructed by themselves, subspace clustering (SC) methods have achieved great success. Generally, SC methods contain some parameters to be tuned, and different affinity matrices can obtain with different parameter values. In this paper, for the first time, we study a method for fusing these different affinity matrices to promote clustering performance and provide the corresponding solution from a multi-view clustering (MVC) perspective. That is, we argue that the different affinity matrices are consistent and complementary, which is similar to the fundamental assumption of MVC methods. Based on this observation, in this paper, we use least squares regression (LSR), which is a typical SC method, as an example since it can be efficiently optimized and has shown good clustering performance and we propose a novel robust least squares regression method from an MVC perspective (RLSR/MVCP). Specifically, we first utilize LSR with different parameter values to obtain different affinity matrices. Then, to fully explore the information contained in these different affinity matrices and to remove noise, we further fuse these affinity matrices into a tensor, which is constrained by the tensor low-rank constraint, i.e., the tensor nuclear norm (TNN). The two steps are combined into a framework that is solved by the augmented Lagrange multiplier (ALM) method. The experimental results on several datasets indicate that RLSR/MVCP has very encouraging clustering performance and is superior to state-of-the-art SC methods.

16.
Neural Netw ; 178: 106434, 2024 Jun 16.
Article in English | MEDLINE | ID: mdl-38941739

ABSTRACT

Low-rank representation (LRR) is a classic subspace clustering (SC) algorithm, and many LRR-based methods have been proposed. Generally, LRR-based methods use denoized data as dictionaries for data reconstruction purpose. However, the dictionaries used in LRR-based algorithms are fixed, leading to poor clustering performance. In addition, most of these methods assume that the input data are linearly correlated. However, in practice, data are mostly nonlinearly correlated. To address these problems, we propose a novel adaptive kernel dictionary-based LRR (AKDLRR) method for SC. Specifically, to explore nonlinear information, the given data are mapped to the Hilbert space via the kernel technique. The dictionary in AKDLRR is not fixed; it adaptively learns from the data in the kernel space, making AKDLRR robust to noise and yielding good clustering performance. To solve the AKDLRR model, an efficient procedure including an alternative optimization strategy is proposed. In addition, a theoretical analysis of the convergence performance of AKDLRR is presented, which reveals that AKDLRR can converge in at most three iterations under certain conditions. The experimental results show that AKDLRR can achieve the best clustering performance and has excellent speed in comparison with other algorithms.

17.
J Cataract Refract Surg ; 50(6): 565-571, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38350161

ABSTRACT

PURPOSE: To explore the influence of preoperative factors, including varying pupil sizes and refractive attributes, on postoperative glare disability in patients undergoing implantable collamer lens (ICL) implantation. SETTING: Second Affiliated Hospital, Nanchang University, Nanchang, Jiangxi, China. DESIGN: Prospective observational study. METHODS: The preoperative ocular characteristics and 6-month postoperative glare status in eligible patients who underwent EVO-Visian ICL V4c (VICMO) implantation were analyzed. The glare disability criteria encompassed a glare symptom score >6 and glare sensitivity exceeding 1:2.7. Logistic regression analysis was used to explore the relationship between the preoperative ocular parameters and post-ICL glare. RESULTS: The study included 95 patients (mean age, 26.04 ± 6.29 years), comprising 30 men (58 eyes) and 65 women (129 eyes). Multivariate analysis revealed a significant correlation between postoperative glare disability and increased spherical power in preoperative mesopic pupils (ß = -0.124, P = .039), as well as elevated cylinder power in preoperative mesopic (ß = -0.412, P = .009) and photopic pupils (ß = -0.430, P = .007). Moreover, a larger preoperative mesopic pupil diameter (ß = 0.561, P = .005) demonstrated a significant correlation with glare disability. CONCLUSIONS: Preoperative mesopic pupil dimensions and associated refractive parameters, such as sphere and cylinder, were correlated with glare disability, including the cylinder aspect in photopic pupils, which can assist clinicians in optimizing preoperative selection for ICL implantation, aiding in the anticipation of potential glare disability risks.


Subject(s)
Glare , Lens Implantation, Intraocular , Mesopic Vision , Phakic Intraocular Lenses , Pupil , Visual Acuity , Adult , Female , Humans , Male , Young Adult , Mesopic Vision/physiology , Myopia/surgery , Myopia/physiopathology , Prospective Studies , Pupil/physiology , Refraction, Ocular/physiology , Risk Factors , Vision Disorders/physiopathology , Visual Acuity/physiology
18.
bioRxiv ; 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-39026842

ABSTRACT

Current treatments for advanced prostate cancer (PCa) primarily target androgen receptor (AR)-pathways. However, the emergence of castration-resistant prostate cancer (CRPC) and resistance to AR signaling inhibitors (ARSI) remains a significant clinical challenge. This study introduces BSJ-5-63, a novel triple degrader targeting cyclin-dependent kinases (CDKs) CDK12, CDK7, and CDK9, with potential to transform CRPC therapy. BSJ-5-63 effectively downregulates homologous recombination repair (HRR) genes, including BRCA1 and BRCA2, through CDK12 degradation, and attenuates AR signaling through CDK7 and CDK9 degradation, further enhancing its therapeutic impact. Importantly, BSJ-5-63 induces a "BRCAness" state that persists for a significant duration, enabling sequential combination therapy with PARP inhibitors (PARPis) while potentially minimizing drug-related toxicity and resistance. In both in vitro and in vivo studies, BSJ-5-63 exhibited potent antiproliferative effects in both AR-positive and AR-negative CRPC models. This study presents a promising multi-pronged approach for CRPC treatment, addressing both DNA repair mechanisms and AR signaling, with the potential to benefit a wide range of patients regardless of their BRCA1/2 mutational status. SIGNIFICANCE: This study introduces BSJ-5-63, a triple degrader designed to target CDK12, CDK7, and CDK9, making a significant advancement in CRPC therapy. The distinctive mechanism of BSJ-5-63 involves downregulating HRR genes and inhibiting AR signaling, thereby inducing a BRCAness state. This enhances sensitivity to PARP inhibition, effectively addressing ARSI resistance and improving the overall efficacy of treatment. The development of BSJ-5-63 represents a promising therapeutic approach, with the potential to benefit a broad spectrum of CRPC patients.

19.
J Biomech ; 166: 112057, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38520934

ABSTRACT

Enhanced external counterpulsation (EECP) is a treatment and rehabilitation approach for ischemic diseases, including coronary artery disease. Its therapeutic benefits are primarily attributed to the improved blood circulation achieved through sequential mechanical compression of the lower extremities. However, despite the crucial role that hemodynamic effects in the lower extremity arteries play in determining the effectiveness of EECP treatment, most studies have focused on the diastole phase and ignored the systolic phase. In the present study, a novel siphon model (SM) was developed to investigate the interdependence of several hemodynamic parameters, including pulse wave velocity, femoral flow rate, the operation pressure of cuffs, and the mean blood flow changes in the femoral artery throughout EECP therapy. To verify the accuracy of the SM, we coupled the predicted afterload in the lower extremity arteries during deflation using SM with the 0D-1D patient-specific model. Finally, the simulation results were compared with clinical measurements obtained during EECP therapy to verify the applicability and accuracy of the SM, as well as the coupling method. The precision and reliability of the previously developed personalized approach were further affirmed in this study. The average waveform similarity coefficient between the simulation results and the clinical measurements during the rest state exceeded 90%. This work has the potential to enhance our understanding of the hemodynamic mechanisms involved in EECP treatment and provide valuable insights for clinical decision-making.


Subject(s)
Counterpulsation , Pulse Wave Analysis , Humans , Reproducibility of Results , Hemodynamics , Lower Extremity , Counterpulsation/methods
20.
Comput Methods Programs Biomed ; 250: 108191, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38677079

ABSTRACT

BACKGROUND AND OBJECTIVE: Enhanced external counterpulsation (EECP) is a mechanically assisted circulation technique widely used in the rehabilitation and management of ischemic cardiovascular diseases. It contributes to cardiovascular functions by regulating the afterload of ventricle to improve hemodynamic effects, including increased diastolic blood pressure at aortic root, increased cardiac output and enhanced blood perfusion to multiple organs including coronary circulation. However, the effects of EECP on the coupling of the ventricle and the arterial system, termed ventricular-arterial coupling (VAC), remain elusive. We aimed to investigate the acute effect of EECP on the dynamic interaction between the left ventricle and its afterload of the arterial system from the perspective of ventricular output work. METHODS: A neural network assisted optimization algorithm was proposed to identify the ordinary differential equation (ODE) relation between aortic root blood pressure and flow rate. Based on the optimized order of ODE, a lumped parameter model (LPM) under EECP was developed taking into consideration of the simultaneous action of cardiac and EECP pressure sources. The ventricular output work, in terms of aortic pressure and flow rate cooperated with the LPM, was used to characterize the VAC of ventricle and its afterload. The VAC subjected to the principle of minimal ventricular output work was validated by solving the Euler-Poisson equation of cost function, ultimately determining the waveforms of aortic pressure and flow rate. RESULTS: A third-order ODE can precisely describe the hemodynamic relationship between aortic pressure and flow rate. An optimized dual-source LPM with three energy-storage elements has been constructed, showing the potential in probing VAC under EECP. The LPM simulation results demonstrated that the VAC in terms of aortic pressure and flow rate yielded to the minimal ventricular output work under different EECP pressures. CONCLUSIONS: The ventricular-arterial coupling under EECP is subjected to the minimal ventricular output work, which can serve as a criterion for determining aortic pressure and flow rate. This study provides insight for the understanding of VAC and has the potential in characterizing the performance of the ventricular and arterial system under EECP.


Subject(s)
Algorithms , Counterpulsation , Heart Ventricles , Hemodynamics , Models, Cardiovascular , Humans , Counterpulsation/methods , Cardiac Output , Arteries/physiology , Blood Pressure , Computer Simulation , Aorta/physiology , Neural Networks, Computer
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